I'm starting to see the new people come in now on 1.23 as "Mildred Resident" or "Herbert456 Resident" and then I see them in my transaction as just their first name like "Twinkletoes".
But what happens if multiple people chose the name "Twinkletoes"? They can't have two "Twinkletoes Residents" and more to the point, they can't have a unique name for their creations, should they make them.
How will that work? Or does the system reject you if you type in "Joe123" and there is already a "Joe123" as a user name?
Usernames must be unique. They can't contain a period, and they can't be the same as an existing user's name with or without a period. For instance, no one can get the username "prokofyneva".
Display names on other hand... everyone in SL could have the display name "Prokofy Neva" or "Twinkletoes". People could have parties where everyone has the same display name, if they like.
Don't expect it to make sense.